Answer: x = 30°
Concept:
Here, we need to know the idea of an isosceles triangle and the vertical angle theorem.
An <u>isosceles triangle</u> is a triangle that has any two of its sides equal to each other. Also, the angles opposite these equal sides are equal, which is basically the base angles.
The <u>vertical angle theorem</u> states that two vertical angles formed when two lines intersect each other are always equal to each other.
Solve:
<u>Find the other base angle of the isosceles triangle.</u>
Since there are two equal sides, we know that this is an isosceles triangle.
Since the definition said that the base angles are equal, the other base angle would also be x.
<u>Find the value of x</u>
According to the vertical angle theorem, two vertical angles formed by intersection are equal.
Just as angle x and 30°, are vertical angles formed by intersection, therefore,
Hope this helps!! :)
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